Semiconductor laser device for improving optical gain by using quantum tunneling capability and preparation method thereof

Abstract

The invention relates to a semiconductor laser device for improving optical gain by using quantum tunneling capability and a preparation method of the semiconductor laser device. The device sequentially comprises a substrate, a buffer layer, a lower transition layer, a lower limiting layer, a lower waveguide layer, a Gax2In1-x2P first quantum well, (Ala1Ga1-a1) b1In1-b1P / (Ala2Ga1-a2) b2In1-b2P strain multi-quantum well barrier superlattice, a Gax3In1-x3P second quantum well, an upper waveguide layer, a first upper limiting layer, a corrosion stop layer, a second upper limiting layer, a first upper transition layer, a second upper transition layer and a cap layer from bottom to top. 0.4 < = x2 < = 0.65; 0.4 < = x3 < = 0.65; 0.6 < = a1 < = 1, 0.38 < = b1 < = 0.48; 0 < = a2 < = 0.4, and 0.5 < = b2 < = 0.65. By using the multi-quantum well barrier structure, the conduction band gap is improved, the carrier overflow is inhibited, and the optical gain is improved.

Description

Technical Field

[0001] The invention relates to a semiconductor laser device which utilizes quantum tunneling capability to improve optical gain and a preparation method thereof, belonging to the technical field of optoelectronics. Background Art

[0002] AlGaInP red light semiconductor lasers are small in size, light in weight, low in power consumption, can be directly modulated, and have high efficiency and reliability. They have broad application prospects in the fields of short-distance all-optical network applications in plastic optical fiber transmission, medical cosmetology, laser display, and industrial measurement. However, the maximum conduction band energy gap difference in the AlGaInP laser material structure is only 270meV, the electron confinement ability is poor, and the electron overflow is more serious. At the same time, AlGaInP has a large thermal resistivity and poor heat dissipation ability. As the output power and working environment increase, the temperature of the active area increases, further deteriorating the carrier confinement ability, resulting in an increase in threshold current, a decrease in slope efficiency, and more waste heat, which limits the further increase in output power.

[0003] The IEEE Journal of selected topics in quantum electronics, Vol 17(6), 2011, Pg 1723–1726 points out that reducing the threshold current density helps to suppress carrier overflow. Among them, AlInP is used as the confinement layer with the maximum light confinement factor, thereby reducing the threshold current density. In AlGaInP materials, the conduction band gap gradually increases with the increase of Al content. It is generally believed that when the Al content reaches (Al70Ga30)50In50P, the material changes from a direct band gap to an indirect band gap, the conduction band is lowered, and the carrier confinement ability becomes worse.

[0004] Japanese Journal of Applied Physics, Vol 45, 2006, Pg 7600–7604 reported that the use of 5 pairs of tensile strain (Al 70 Ga 30 ) 0.5 In 0.5 P and compressive strained GaInP are grown alternately to suppress electron overflow, reduce threshold current density, and improve slope efficiency. The literature Laser Diode Technology and Applications, Vol 1850, 1993, Pg 263–269 reported the use of lattice matching (Al 70 Ga 30 ) 0.5 In 0.5P and GaInP are alternately grown in a superlattice structure to increase the conduction band gap and suppress electron overflow, thereby improving slope efficiency. Although the use of a superlattice multi-quantum well barrier structure to form an electronic reflection structure (MQB) can increase the conduction band gap and suppress the carrier confinement capability, the use of AlGaInP as a confinement layer reduces the refractive index difference with the quantum well, and the light confinement capability becomes poor, resulting in a larger threshold current and a reduced optical gain.

[0005] The literature Chinese Laser, Vol 42(7), 2020, Pg 0701007-1-13 reviews the principles and latest developments of quantum cascade lasers. Unlike conventional semiconductor lasers, quantum cascade lasers use electron transitions between quantized energy bands and photon-assisted quantum tunneling of electrons through a series of quantum wells under bias to achieve light amplification, that is, electrons transition from the ground state of one quantum well to the excited state of an adjacent quantum well under bias, accompanied by photon emission. However, QCL requires the growth of thousands of layers of monolayer materials, and has high requirements for thickness, composition, and growth stability, and lacks the application of this principle in conventional quantum well lasers.

[0006] Chinese patent document CN115528542A discloses an AlGaInP red light semiconductor laser device with a strained superlattice structure and a preparation method thereof. The device inserts a strained superlattice between the component gradient waveguide layer structure and the quantum well, utilizes the principle of the strained superlattice to suppress defects and non-radiative recombination, improves the material growth quality, and improves the aging characteristics. However, the structure is located between the N waveguide layer and the quantum well, and has no effect on suppressing the overflow of the quantum well into the P confinement layer. At the same time, the components of each pair of materials are fixed, and the quantum tunneling effect is poor. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a semiconductor laser device and a preparation method thereof that utilizes quantum tunneling capability to improve optical gain;

[0008] In the present invention, AlInP is used as a limiting layer to achieve the highest refractive index difference design, improve the light limiting ability, and reduce the threshold current; a multi-quantum well barrier structure (MQB) is used as a barrier layer to increase the conduction band gap of the barrier layer between the multi-quantum wells and enhance the electron suppression ability; the multi-quantum well barrier structure (MQB) adopts thin layer strain technology to achieve band quantization, and uses the energy band tilt quantum tunneling under bias to reduce the threshold current and improve the optical gain. The multi-quantum well barrier structure (MQB) adopts component gradient technology to increase the energy band tilt under bias, accelerate quantum tunneling, and improve the optical gain.

[0009] The technical solution of the present invention is as follows:

[0010] In a first aspect, the present invention provides a semiconductor laser device that utilizes quantum tunneling capability to increase optical gain.

[0011] A semiconductor laser device that utilizes quantum tunneling capability to increase optical gain, comprising, from bottom to top, a substrate, a buffer layer, a lower transition layer, a lower confinement layer, a lower waveguide layer, and a Ga x2 In 1-x2 P first quantum well, (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice, Ga x3 In 1-x3 P second quantum well, upper waveguide layer, first upper confinement layer, corrosion stop layer, second upper confinement layer, first upper transition layer, second upper transition layer and cap layer;

[0012] Among them, 0.4≤x2≤0.65; 0.4≤x3≤0.65; 0.6≤a1≤1, 0.38≤b1≤0.48; 0≤a2≤0.4, 0.5≤b2≤0.65.

[0013] According to the preferred embodiment of the present invention, the Ga x2 In 1-x2 P first quantum well, unintentionally doped, with a thickness of 4-15nm; further preferably, x2=0.43, the Ga x2 In 1-x2 The thickness of the first quantum well P is 5nm.

[0014] According to the preferred embodiment of the present invention, the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multi-quantum well barrier superlattice, unintentionally doped, with a thickness of 1-5nm; at the same time, between the first pair and the Nth pair, a1 and a2 are gradually reduced to maintain the difference between a1 and a2.

[0015] Further preferably, the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2In the P strained multi-quantum well barrier superlattice, the first pair has a1=0.95, b1=0.42, a thickness of 1.12nm, a2=0.25, b2=0.55, a thickness of 1.46nm; the second pair has a1=0.92, b1=0.42, a thickness of 1.17nm, a2=0.22, b2=0.55, a thickness of 1.51nm; the third pair has a1=0.9, b1=0.42, a thickness of 1.23nm, a2=0.2, b2=0.55, a thickness of 1.58nm m; the fourth pair a1=0.88, b1=0.42, thickness is 1.3nm, a2=0.18, b2=0.55, thickness is 1.65nm; the fifth pair a1=0.85, b1=0.42, thickness is 1.35nm, a2=0.15, b2=0.55, thickness is 1.73nm; the sixth pair a1=0.82, b1=0.42, thickness is 1.43nm, a2=0.18, b2=0.55, thickness is 1.81nm; there are 6 pairs of alternating growth.

[0016] According to the preferred embodiment of the present invention, the Ga x3 In 1-x3 P second quantum well, unintentionally doped, 0.4≤x3≤0.65, thickness 4-15nm;

[0017] Further preferably, x3=0.43, the quantum well thickness is 5 nm, and the lasing wavelength is 645 nm.

[0018] According to the preferred embodiment of the present invention, the lower limiting layer is n-type Al 0.5 In 0.5 P lower limiting layer, the first upper limiting layer is P-type Al 0.5 In 0.5 The first upper limiting layer is P, and the second upper limiting layer is P-type Al 0.5 In 0.5 P second upper confinement layer.

[0019] According to the preferred embodiment of the present invention, the n-type Al 0.5 In 0.5 The doping source of the lower confinement layer of P is Si 2 H 6 , doping concentration is 3E17-1.5E18 atoms / cm 3 , thickness is 0.5-3μm;

[0020] Further preferably, the n-type Al 0.5 In 0.5 The thickness of the P lower confinement layer is 0.9 μm and the doping concentration is 7E17 atoms / cm 3 .

[0021] According to the preferred embodiment of the present invention, the P-type Al0.5 In 0.5 The doping source of the first upper confinement layer is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.1-0.5μm;

[0022] Further preferably, the P-type Al 0.5 In 0.5 The thickness of the first upper confinement layer is 0.2 μm, and the doping concentration is 5E17 atoms / cm 3 .

[0023] According to the preferred embodiment of the present invention, the P-type Al 0.5 In 0.5 The doping source of the second upper confinement layer is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.5-2μm;

[0024] Further preferably, the P-type Al 0.5 In 0.5 The thickness of the second upper confinement layer is 0.8 μm, and the doping concentration is 8E17 atoms / cm 3 .

[0025] According to the preferred embodiment of the present invention, the substrate is a GaAs substrate, the buffer layer is a GaAs buffer layer, and the lower transition layer is a Ga 0.5 In 0.5 P lower transition layer, the lower waveguide layer is (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer, the upper waveguide layer is (Al x4 Ga 1-x4 ) y2 In 1-y2 P waveguide layer, the corrosion stop layer is P-type Ga x5 In 1-x5 P corrosion stop layer, the first upper transition layer is (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P is the first upper transition layer, and the second upper transition layer is Ga 0.5 In 0.5 P second upper transition layer, the cap layer is a GaAs cap layer;

[0026] Among them, 0.4≤x1≤1, 0.4≤y1≤0.6; 0.4≤x4≤1, 0.4≤y2≤0.6; 0.5≤x5≤0.6.

[0027] According to the preferred embodiment of the present invention, the doping source of the GaAs buffer layer is Si 2 H 6 , doping concentration is 2E18-5E18 atoms / cm 3 , thickness is 0.1-0.3μm;

[0028] Further preferably, the thickness of the GaAs buffer layer is 0.2 μm and the doping concentration is 2E18 atoms / cm 3 .

[0029] According to the preferred embodiment of the present invention, the Ga 0.5 In 0.5 The doping source of the P lower transition layer is Si 2 H 6 , doping concentration is 5E17-2E18 atoms / cm 3 , thickness is 0.1-0.3μm;

[0030] Further preferably, the Ga 0.5 In 0.5 The thickness of the P lower transition layer is 0.1 μm and the doping concentration is 1E18 atoms / cm 3 .

[0031] According to the preferred embodiment of the present invention, the (Al x1 Ga 1-x1 ) y1 In 1-y1 The waveguide layer below P is not intentionally doped, 0.4≤x1≤1, 0.4≤y1≤0.6, x1 gradually changes from less than 1 to greater than or equal to 0.4, and the thickness is 60-200nm;

[0032] Further preferably, the (Al x1 Ga 1-x1 ) y1 In 1-y1 In the waveguide layer below P, x1 changes gradually from 0.95 to 0.5, y1=0.5, and the thickness is 100nm.

[0033] According to the preferred embodiment of the present invention, the (Al x4 Ga 1-x4 ) y2 In 1-y2 The waveguide layer on P is not intentionally doped, 0.4≤x4≤1, 0.4≤y2≤0.6, x4 gradually changes from greater than or equal to 0.4 to less than or equal to 1, and the thickness is 60-200nm;

[0034] Further preferably, the (Al x4 Ga 1-x4 ) y2 In 1-y2In the waveguide layer on P, x4 changes gradually from 0.5 to 0.95, y2=0.5, and the thickness is 100nm.

[0035] According to the preferred embodiment of the present invention, the P-type Ga x5 In 1-x5 The doping source of the P corrosion stop layer is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , 0.5≤x5≤0.6, thickness is 5-30nm;

[0036] Further preferably, the P-type Ga x5 In 1-x5 The thickness of the P etch stop layer is 10 nm, x5 = 0.53, and the doping concentration is 2E18 atoms / cm 3 .

[0037] According to the preferred embodiment of the present invention, the (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The doping source of the first upper transition layer of P is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm;

[0038] Further preferably, the (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The thickness of the first upper transition layer of P is 20nm, and the doping concentration is 1.2E18 atoms / cm 3 .

[0039] According to the preferred embodiment of the present invention, the Ga 0.5 In 0.5 The doping source of the second upper transition layer of P is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm;

[0040] Further preferably, the Ga 0.5 In 0.5 The thickness of the second upper transition layer of P is 20nm, and the doping concentration is 1.5E18 atoms / cm 3 .

[0041] According to the preferred embodiment of the present invention, the doping source of the GaAs cap layer is CBr4 or DEZn, and the doping concentration is 3E19-1E20 atoms / cm 3 , thickness is 100-500nm;

[0042] Further preferably, the thickness of the GaAs cap layer is 200 nm and the doping concentration is 5E19 atoms / cm 3 .

[0043] The second aspect of the present invention provides a method for preparing the semiconductor laser device that utilizes quantum tunneling capability to increase optical gain.

[0044] The method for preparing the semiconductor laser device using quantum tunneling capability to improve optical gain comprises:

[0045] Growing the buffer layer, the lower transition layer, the lower confinement layer, and the lower waveguide layer in sequence on the substrate;

[0046] The Ga is grown on the lower waveguide layer. x2 In 1-x2 P first quantum well; including: the temperature is maintained at 650±10℃, TMIn, TMGa and PH are introduced 3 , the Ga x2 In 1-x2 P first quantum well;

[0047] In the Ga x2 In 1-x2 The (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1- b2 P strained multi-quantum well barrier superlattice; including: the temperature is maintained at 650±10℃, TMAl, TMIn, TMGa and PH are introduced 3 , in the Ga 1-x2 In x2 The (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice;

[0048] In the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2The GaP strained multi-quantum well barrier superlattice was grown on x3 In 1-x3 P second quantum well; including: the temperature is maintained at 650±10℃, TMIn, TMGa and PH are introduced 3 , in the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 The GaP strained multi-quantum well barrier superlattice was grown on x3 In 1-x3 P second quantum well;

[0049] In the Ga x3 In 1-x3 The upper waveguide layer, the first upper confinement layer, the corrosion stop layer, the second upper confinement layer, the first upper transition layer, the second upper transition layer and the cap layer are sequentially grown on the P second quantum well.

[0050] According to the preferred embodiment of the present invention, a GaAs buffer layer, a GaAs layer and a GaAs layer are sequentially grown on a GaAs substrate. 0.5 In 0.5 P lower transition layer, n-type Al 0.5 In 0.5 P lower confinement layer, (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer; including:

[0051] S1, place the GaAs substrate in the growth chamber of the MOCVD equipment, H 2 The environment temperature was raised to 720±10℃ and baked, and AsH 3 , performing surface heat treatment on the GaAs substrate;

[0052] S2, slowly lowering the temperature to 680±10° C., with a cooling rate of no more than 30° C. / min, continuing to introduce TMGa and AsH 3 to grow a GaAs buffer layer on the GaAs substrate;

[0053] S3, the temperature is maintained at 680±10°C, the growth is stopped on the GaAs buffer layer, and PH 3 , the growth is paused by stopping the V group source and the III group source for 3-30 seconds to deplete the As atoms in the growth chamber of the MOCVD equipment;

[0054] S4, the temperature is maintained at 680±10℃, TMGa, TMIn and PH are introduced 3, Ga is grown on the GaAs buffer layer 0.5 In 0.5 P lower transition layer;

[0055] S5, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, and TMAl, TMIn and PH are introduced. 3 , in the Ga 0.5 In 0.5 Growth of n-type Al on the transition layer below P 0.5 In 0.5 P lower limiting layer.

[0056] S6, the temperature is slowly changed to 650±10℃, the cooling rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and PH are introduced 3 , in n-type Al 0.5 In 0.5 Growth on the confinement layer below P (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer.

[0057] According to the preferred embodiment of the present invention, in the Ga x3 In 1-x3 P second quantum well is grown in sequence (Al x4 Ga 1-x4 ) y2 In 1-y2 P upper waveguide layer, P type Al 0.5 In 0.5 P first upper confinement layer, P-type Ga x5 In 1-x5 P corrosion stop layer, P type Al 0.5 In 0.5 P second upper limiting layer,

[0058] (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer, Ga 0.5 In 0.5 P second upper transition layer and GaAs cap layer; including:

[0059] S7, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and PH are continuously introduced. 3 , in Ga x3 In 1-x3 The second quantum well of P is grown on x4 Ga 1-x4 ) y2 In1-y2 P upper waveguide layer.

[0060] S8, the temperature is maintained at 700±10℃, and TMAl, TMIn and PH are continuously introduced. 3 , in the (Al x4 Ga 1-x4 ) y2 In 1-y2 P-type Al is grown on the P upper waveguide layer 0.5 In 0.5 P first upper confinement layer;

[0061] S9, the temperature is maintained at 700±10℃, and TMGa, TMIn and PH are continuously introduced. 3 , in the P-type Al 0.5 In 0.5 P-type Ga is grown on the first upper confinement layer x5 In 1-x5 P corrosion stop layer;

[0062] S10, the temperature is maintained at 700±10℃, and TMAl, TMIn and PH are continuously introduced. 3 , in the P-type Ga x5 In 1-x5 Growth of P-type Al on P Etch Stop Layer 0.5 In 0.5 P second upper limiting layer;

[0063] S11, the temperature is gradually changed to 680±10℃, the cooling rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and AsH are introduced. 3 , in the P-type Al 0.5 In 0.5 P second upper confinement layer growth (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer;

[0064] S12, the temperature is maintained at 680±10℃, the cooling rate is not higher than 60℃ / min, and TMIn, TMGa and AsH are introduced. 3 , in the (Al 0.5 Ga 0.5 ) 0.5 In 0.5 Ga is grown on the first upper transition layer 0.5 In 0.5 P second upper transition layer;

[0065] S13, lower the temperature to 540±10°C, with the cooling rate not exceeding 40°C / min, continue to introduce TMGa and AsH3,0.5 In 0.5 A GaAs cap layer is grown on the P second upper transition layer.

[0066] The beneficial effects of the present invention are:

[0067] 1. Use the multi-quantum well barrier structure (MQB) as the barrier layer to increase the conduction band gap of the barrier layer between the multi-quantum wells, enhance the electron suppression ability, and improve the high-temperature reliability;

[0068] 2. The multiple quantum well barrier structure (MQB) adopts thin-layer strain technology to achieve band quantization, and utilizes band tilt quantum tunneling under bias to reduce the threshold current and increase the optical gain. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Figure 1 A schematic diagram showing a design comparison between a conventional laser device structure (left side) and a semiconductor laser device structure with improved optical gain through quantum tunneling capability of the present invention (right side);

[0070] Figure 2 A schematic diagram showing a comparison of PI test curves at different temperatures between a conventional laser device structure (solid line) and a semiconductor laser device structure (dashed line) of the present invention with improved light gain through quantum tunneling capability;

[0071] Among them, 1. GaAs substrate, 2. GaAs buffer layer, 3. Ga 0.5 In 0.5 P lower transition layer, 4, n-type Al 0.5 In 0.5 P lower limiting layer, 5, (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer, 6, Ga x2 In 1-x2 P first quantum well, 7, (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice, 8, Ga x3 In 1-x3 P second quantum well, 9, (Al x4 Ga 1-x4 ) y2 In 1-y2 P upper waveguide layer, 10, P-type Al 0.5 In 0.5 P first upper confinement layer, 11, Ga x5 In 1-x5P corrosion stop layer, 12, P type Al 0.5 In 0.5 P second upper confinement layer, 13, (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer, 14, Ga 0.5 In 0.5 P second upper transition layer, 15, GaAs cap layer. DETAILED DESCRIPTION

[0072] The present invention will be further defined below in conjunction with the accompanying drawings and embodiments, but is not limited thereto.

[0073] Example 1

[0074] A semiconductor laser device that utilizes quantum tunneling capability to increase optical gain, comprising, from bottom to top, a substrate, a buffer layer, a lower transition layer, a lower confinement layer, a lower waveguide layer, and a Ga x2 In 1-x2 P first quantum well 6, (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice 7, Ga x3 In 1-x3 P second quantum well 8, upper waveguide layer, first upper confinement layer, corrosion stop layer, second upper confinement layer, first upper transition layer, second upper transition layer and cap layer;

[0075] Among them, 0.4≤x2≤0.65; 0.4≤x3≤0.65; 0.6≤a1≤1, 0.38≤b1≤0.48; 0≤a2≤0.4, 0.5≤b2≤0.65.

[0076] The barrier layer is (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P multiple quantum well barrier uses electron reflection to increase the conduction band gap, inhibit the thermal diffusion of carriers from the first quantum well to the second quantum well, and reduce the carrier density in the second quantum well, thereby reducing the thermal escape of carriers caused by radiation recombination;

[0077] (Al a1 Ga 1-a1 )b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 The P multi-quantum well barrier adopts ultra-thin layer strain growth technology to achieve band quantization, and uses quantum tunneling under bias to reduce the carrier inversion threshold in the second quantum well, which is conducive to the lasing of the second quantum well, reduces the threshold current and improves the optical gain.

[0078] (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 In the growth of multiple pairs of P multi-quantum well barriers, the a1 component decreases step by step, and the a2 component decreases step by step, which ensures the refractive index difference while forming a structure with gradually decreasing band gap, accelerates quantum tunneling under bias, improves carrier utilization, and improves optical gain.

[0079] The greater the difference between a1 and a2, the more obvious the electron reflection effect achieved by the multi-quantum well barrier. When b1 is less than or equal to 0.48, the material is subjected to compressive strain, the band gap separation causes the conduction band to move upward, which helps to improve the conduction band gap difference. At the same time, b2 is greater than or equal to 0.5, the material is subjected to tensile strain, which not only achieves strain compensation to avoid defects, but also stress helps to quantize energy levels and realize quantum tunneling.

[0080] Figure 1 Schematic diagram for comparing the conventional laser device structure (left) and the semiconductor laser device structure (right) of the present invention with improved light gain through quantum tunneling capability; as can be seen from the comparative structure, the present invention replaces the conventional barrier layer structure with (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 The P strained multi-quantum well barrier superlattice 7, through reasonable structural design, helps to improve the carrier suppression capability, reduce the threshold current and increase the optical gain.

[0081] Example 2

[0082] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to Embodiment 1 is different in that:

[0083] Ga x2 In 1-x2P first quantum well 6, unintentionally doped, with a thickness of 4-15nm; the quantum well composition and thickness are designed according to the needs to achieve the required lasing wavelength;

[0084] (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multi-quantum well barrier superlattice 7, unintentionally doped, with a thickness of 1-5nm; if the thickness is too small, the MOCVD growth technology will find it difficult to control the growth interface, and if the thickness is too large, the quantum effect will be weakened and it will be difficult to achieve the tunneling effect. At the same time, between the first pair and the Nth pair, a1 and a2 are gradually reduced to maintain the difference between a1 and a2. The electron reflection effect is guaranteed, but due to the reduction of a1 and a1 components, the band gap is reduced, and the energy band tilt effect under bias is more obvious, which is conducive to quantum tunneling.

[0085] Ga x3 In 1-x3 The second quantum well P 8 is not intentionally doped, 0.4≤x3≤0.65, and has a thickness of 4-15nm. The quantum well composition and thickness are designed according to needs to achieve the required lasing wavelength.

[0086] Example 3

[0087] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to Embodiment 2 is different in that:

[0088] x2=0.43,Ga x2 In 1-x2 The thickness of the first quantum well 6 is 5 nm, and the lasing wavelength is 645 nm.

[0089] (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2In the P strained multi-quantum well barrier superlattice 7, the first pair has a1=0.95, b1=0.42, a thickness of 1.12nm, a2=0.25, b2=0.55, a thickness of 1.46nm; the second pair has a1=0.92, b1=0.42, a thickness of 1.17nm, a2=0.22, b2=0.55, a thickness of 1.51nm; the third pair has a1=0.9, b1=0.42, a thickness of 1.23nm, a2=0.2, b2=0.55, a thickness of 1.58 nm; the fourth pair a1 = 0.88, b1 = 0.42, thickness is 1.3nm, a2 = 0.18, b2 = 0.55, thickness is 1.65nm; the fifth pair a1 = 0.85, b1 = 0.42, thickness is 1.35nm, a2 = 0.15, b2 = 0.55, thickness is 1.73nm; the sixth pair a1 = 0.82, b1 = 0.42, thickness is 1.43nm, a2 = 0.18, b2 = 0.55, thickness is 1.81nm; a total of 6 pairs are grown alternately. By using this structural design, the conduction band gap difference can be improved, the overflow of carriers from the first quantum well to the second quantum well can be suppressed, the carrier density in the second quantum well can be reduced, and the heat escape caused by the heating of the radiation recombination can be reduced. At the same time, the tunneling effect can be used to realize quantum tunneling, and the particle number inversion lasing can be realized in the second quantum well, which is helpful to reduce the threshold current and improve the optical gain.

[0090] x3=0.43, the quantum well thickness is 5nm, and the lasing wavelength is 645nm.

[0091] Figure 2 A schematic diagram showing a comparison of PI test curves at different temperatures between a conventional laser device structure (solid line) and a semiconductor laser device structure (dashed line) of the present invention with improved light gain through quantum tunneling capability;

[0092] Among them, the solid line is the conventional structure, the dotted line is the structure of the present invention, the horizontal axis is the working current (unit A), and the vertical axis is the output power (unit W). From the comparison results, it can be seen that the structure of the present invention has no obvious advantages at room temperature 25°C, but as the working temperature increases, the carrier suppression ability of the present invention is better, and it has higher output power at high temperature. The lack of obvious advantages at room temperature may be related to the growth quality of the multi-thin layer well barrier structure, which needs to be further optimized.

[0093] Example 4

[0094] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to any one of embodiments 1 to 3 is different in that:

[0095] The lower confinement layer is n-type Al 0.5 In 0.5 P lower limiting layer 4, the first upper limiting layer is P-type Al 0.5 In 0.5The first upper limiting layer 10 is P, and the second upper limiting layer is P-type Al 0.5 In 0.5 P second upper confinement layer 12 .

[0096] The limiting layer is made of Al 0.5 In 0.5 P, has the lowest refractive index, has the largest refractive index difference with the quantum well, has a higher light confinement ability, helps to reduce the threshold current and improve the optical gain;

[0097] n-type Al 0.5 In 0.5 The doping source of the P lower confinement layer 4 is Si 2 H 6 , doping concentration is 3E17-1.5E18 atoms / cm 3 , thickness is 0.5-3μm;

[0098] P-type Al 0.5 In 0.5 The doping source of the first upper confinement layer 10 is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.1-0.5μm;

[0099] P-type Al 0.5 In 0.5 The doping source of the second upper confinement layer 12 is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.5-2μm.

[0100] Example 5

[0101] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to Embodiment 4 is different in that:

[0102] n-type Al 0.5 In 0.5 The thickness of the P lower confinement layer 4 is 0.9 μm, and the doping concentration is 7E17 atoms / cm 3 .

[0103] P-type Al 0.5 In 0.5 The thickness of the first upper confinement layer 10 is 0.2 μm, and the doping concentration is 5E17 atoms / cm 3 .

[0104] P-type Al 0.5 In 0.5 The thickness of the second upper confinement layer 12 is 0.8 μm, and the doping concentration is 8E17 atoms / cm 3 .

[0105] Example 6

[0106] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to any one of embodiments 1 to 5 is different in that:

[0107] The substrate is GaAs substrate 1, the buffer layer is GaAs buffer layer, and the lower transition layer is Ga 0.5 In 0.5 P lower transition layer 3, lower waveguide layer is (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer, upper waveguide layer is (Al x4 Ga 1-x4 ) y2 In 1-y2 P waveguide layer 9, the corrosion stop layer is P-type Ga x5 In 1-x5 P corrosion stop layer 11, the first upper transition layer is (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The first upper transition layer is P, and the second upper transition layer is Ga 0.5 In 0.5 P second upper transition layer 14, cap layer is GaAs cap layer 15;

[0108] Among them, 0.4≤x1≤1, 0.4≤y1≤0.6; 0.4≤x4≤1, 0.4≤y2≤0.6; 0.5≤x5≤0.6.

[0109] The doping source of GaAs buffer layer is Si 2 H 6 , doping concentration is 2E18-5E18 atoms / cm 3 , thickness is 0.1-0.3μm;

[0110] Ga 0.5 In 0.5 The doping source of the P lower transition layer 3 is Si 2 H 6 , doping concentration is 5E17-2E18 atoms / cm 3 , thickness is 0.1-0.3μm;

[0111] (Al x1 Ga 1-x1 ) y1 In 1-y1 The waveguide layer below P is not intentionally doped, 0.4≤x1≤1, 0.4≤y1≤0.6, x1 gradually changes from less than 1 to greater than or equal to 0.4, and the thickness is 60-200nm;

[0112] (Al x4 Ga 1-x4 ) y2 In 1-y2 The waveguide layer 9 on P is not intentionally doped, 0.4≤x4≤1, 0.4≤y2≤0.6, x4 gradually changes from greater than or equal to 0.4 to less than or equal to 1, and the thickness is 60-200nm;

[0113] P type Ga x5 In 1-x5 The doping source of the P corrosion stop layer 11 is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , 0.5≤x5≤0.6, thickness is 5-30nm;

[0114] (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The doping source of the first upper transition layer 13 is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm;

[0115] Ga 0.5 In 0.5 The doping source of the second upper transition layer 14 is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm;

[0116] The doping source of the GaAs cap layer 15 is CBr4 or DEZn, and the doping concentration is 3E19-1E20 atoms / cm 3 , thickness is 100-500nm.

[0117] Example 7

[0118] The semiconductor laser device for improving optical gain by using quantum tunneling capability according to Embodiment 6 is different in that:

[0119] The thickness of the GaAs buffer layer is 0.2 μm and the doping concentration is 2E18 atoms / cm 3 .

[0120] Ga 0.5 In 0.5 The thickness of the P lower transition layer 3 is 0.1 μm, and the doping concentration is 1E18 atoms / cm 3 .

[0121] (Al x1 Ga 1-x1 ) y1 In1-y1 In the waveguide layer below P, x1 changes gradually from 0.95 to 0.5, y1=0.5, and the thickness is 100nm.

[0122] (Al x4 Ga 1-x4 ) y2 In 1-y2 In the waveguide layer 9 on P, x4 changes gradually from 0.5 to 0.95, y2=0.5, and the thickness is 100 nm.

[0123] P type Ga x5 In 1-x5 The thickness of the P etching stop layer 11 is 10 nm, x5=0.53, and the doping concentration is 2E18 atoms / cm 3 .

[0124] (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The thickness of the first upper transition layer 13 is 20 nm, and the doping concentration is 1.2E18 atoms / cm 3 .

[0125] Ga 0.5 In 0.5 The thickness of the second upper transition layer 14 is 20 nm, and the doping concentration is 1.5E18 atoms / cm 3 .

[0126] The thickness of the GaAs cap layer 15 is 200 nm and the doping concentration is 5E19 atoms / cm 3 .

[0127] Example 8

[0128] The method for preparing a semiconductor laser device for improving optical gain by using quantum tunneling capability as described in any one of embodiments 1 to 7 comprises:

[0129] sequentially growing a buffer layer, a lower transition layer, a lower confinement layer, and a lower waveguide layer on the substrate;

[0130] Ga is grown on the lower waveguide layer. x2 In 1-x2 P first quantum well 6; including: the temperature is maintained at 650 ± 10 ℃, TMIn, TMGa and PH 3 , Ga is grown on the lower waveguide layer x2 In 1-x2 P first quantum well 6;

[0131] In Ga x2 In 1-x2 P first quantum well 6 is grown (Al a1 Ga1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multi-quantum well barrier superlattice 7; comprising: maintaining the temperature at 650±10°C, introducing TMAl, TMIn, TMGa and PH 3 , in Ga 1-x2 In x2 The first quantum well of P is grown on a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice 7;

[0132] In (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 Growth of Ga on P-strained MQW-7 x3 In 1-x3 P second quantum well 8; including: the temperature is maintained at 650 ± 10 ℃, TMIn, TMGa and PH 3 , in (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 Growth of Ga on P-strained MQW-7 superlattice x3 In 1-x3 P second quantum well 8;

[0133] In Ga x3 In 1-x3 An upper waveguide layer, a first upper confinement layer, an etching stop layer, a second upper confinement layer, a first upper transition layer, a second upper transition layer and a cap layer are sequentially grown on the P second quantum well 8.

[0134] Example 9

[0135] The method for preparing a semiconductor laser device for improving optical gain by using quantum tunneling capability according to Embodiment 8 is different in that:

[0136] The GaAs buffer layer, GaAs buffer layer, and GaAs layer are sequentially grown on the GaAs substrate 1. 0.5 In 0.5 P lower transition layer 3, n-type Al 0.5 In 0.5 P lower limiting layer 4, (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer; including:

[0137] S1, place the GaAs substrate 1 in the growth chamber of the MOCVD equipment, H 2 The environment temperature was raised to 720±10℃ and baked, and AsH 3 , performing surface heat treatment on the GaAs substrate 1;

[0138] S2, slowly lowering the temperature to 680±10°C, with the cooling rate not higher than 30°C / min, continuing to introduce TMGa and AsH3, and growing a GaAs buffer layer 2 on the GaAs substrate 1; the purpose is to prevent defects from propagating from the substrate into the confinement layer, provide a fresh growth interface, and improve the quality of material growth.

[0139] S3, the temperature is maintained at 680±10℃, the growth is stopped on the GaAs buffer layer 2, and PH is introduced 3 By stopping the V group source (99.9999% AsH 3 ) and group III source (TMGa) to achieve growth pause, stop for 3-30s, and deplete As atoms in the growth chamber of the MOCVD equipment;

[0140] S4, the temperature is maintained at 680±10℃, TMGa, TMIn and PH are introduced 3 , Ga is grown on the GaAs buffer layer 2 0.5 In 0.5 P lower transition layer 3; the purpose is to reduce the voltage increase caused by the band gap mutation and increase the electron migration rate.

[0141] S5, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, and TMAl, TMIn and PH are introduced. 3 , in Ga 0.5 In 0.5 n-type Al is grown on the P lower transition layer 3 0.5 In 0.5 P lower confinement layer 4.

[0142] S6, the temperature is slowly changed to 650±10℃, the cooling rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and PH are introduced 3 , in n-type Al 0.5 In 0.5The growth of Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer 5.

[0143] In Ga x3 In 1-x3 P second quantum well 8 is sequentially grown (Al x4 Ga 1-x4 ) y2 In 1-y2 P upper waveguide layer 9, P type Al 0.5 In 0.5 P first upper confinement layer 10, P type Ga x5 In 1-x5 P corrosion stop layer 11, P type Al 0.5 In 0.5 The second upper confinement layer 12 (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer 13, Ga 0.5 In 0.5 P second upper transition layer 14 and GaAs cap layer 15; including:

[0144] S7, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and PH are continuously introduced. 3 , in Ga x3 In 1-x3 P second quantum well 8 is grown (Al x4 Ga 1-x4 ) y2 In 1-y2 Waveguide layer 9 on P.

[0145] S8, the temperature is maintained at 700±10℃, and TMAl, TMIn and PH are continuously introduced. 3 , in (Al x4 Ga 1-x4 ) y2 In 1-y2 P-type Al is grown on the P upper waveguide layer 9 0.5 In 0.5 P first upper confinement layer 10;

[0146] S9, the temperature is maintained at 700±10℃, and TMGa, TMIn and PH are continuously introduced. 3 , in P-type Al 0.5 In 0.5 P-type Ga is grown on the first upper confinement layer 10 x5 In 1-x5 P corrosion stop layer 11;

[0147] S10, the temperature is maintained at 700±10℃, and TMAl, TMIn and PH are continuously introduced. 3 , in P-type Ga x5 In 1-x5 P-type Al is grown on the P etching stop layer 11 0.5 In 0.5 P second upper confinement layer 12;

[0148] S11, the temperature is gradually changed to 680±10℃, the cooling rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and AsH are introduced. 3 , in P-type Al 0.5 In 0.5 The second upper confinement layer 12 grows (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer 13;

[0149] S12, the temperature is maintained at 680±10℃, the cooling rate is not higher than 60℃ / min, and TMIn, TMGa and AsH are introduced. 3 , in (Al 0.5 Ga 0.5 ) 0.5 In 0.5 Ga is grown on the first upper transition layer 13 0.5 In 0.5 P second upper transition layer 14;

[0150] S13, lower the temperature to 540±10℃, the cooling rate should not exceed 40℃ / min, continue to introduce TMGa and AsH3, 0.5 In 0.5 A GaAs cap layer 15 is grown on the P second upper transition layer 14 .

Claims

1. A semiconductor laser device that utilizes quantum tunneling capability to increase optical gain, characterized in that: From bottom to top, it includes substrate, buffer layer, lower transition layer, lower confinement layer, lower waveguide layer, Ga x2 In 1-x2 P first quantum well, (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice, Ga x3 In 1-x3 P second quantum well, upper waveguide layer, first upper confinement layer, corrosion stop layer, second upper confinement layer, first upper transition layer, second upper transition layer and cap layer; Among them, 0.4≤x2≤0.65; 0.4≤x3≤0.65; 0.6≤a1≤1, 0.38≤b1≤0.48; 0≤a2≤0.4, 0.5≤b2≤0.

65.

2. A semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 1, characterized in that: The Ga x2 In 1-x2 P first quantum well, unintentionally doped, thickness 4-15nm; The a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multi-quantum well barrier superlattice, unintentionally doped, with a thickness of 1-5nm; at the same time, between the first pair and the Nth pair, a1 and a2 are gradually reduced, maintaining the difference between a1 and a2; The Ga x3 In 1-x3 P second quantum well, unintentionally doped, 0.4≤x3≤0.65, thickness 4-15nm.

3. A semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 1, characterized in that: x2=0.43,the Ga x2 In 1-x2 The thickness of the first quantum well is 5nm; The a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 In the P strained multi-quantum well barrier superlattice, the first pair has a1=0.95, b1=0.42, a thickness of 1.12nm, a2=0.25, b2=0.55, a thickness of 1.46nm; the second pair has a1=0.92, b1=0.42, a thickness of 1.17nm, a2=0.22, b2=0.55, a thickness of 1.51nm; the third pair has a1=0.9, b1=0.42, a thickness of 1.23nm, a2=0.2, b2=0.55, a thickness of 1.58nm m; the fourth pair a1 = 0.88, b1 = 0.42, thickness 1.3nm, a2 = 0.18, b2 = 0.55, thickness 1.65nm; the fifth pair a1 = 0.85, b1 = 0.42, thickness 1.35nm, a2 = 0.15, b2 = 0.55, thickness 1.73nm; the sixth pair a1 = 0.82, b1 = 0.42, thickness 1.43nm, a2 = 0.18, b2 = 0.55, thickness 1.81nm; alternating growth, a total of 6 pairs; Further preferably, x3=0.43, the quantum well thickness is 5 nm, and the lasing wavelength is 645 nm.

4. A semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 1, characterized in that: The lower confinement layer is n-type Al 0.5 In 0.5 P lower limiting layer, the first upper limiting layer is P-type Al 0.5 In 0.5 The first upper limiting layer is P, and the second upper limiting layer is P-type Al 0.5 In 0.5 P second upper confinement layer.

5. A semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 4, characterized in that: The n-type Al 0.5 In 0.5 The doping source of the P lower confinement layer is Si2H6, and the doping concentration is 3E17-1.5E18 atoms / cm 3 , thickness is 0.5-3μm; The P-type Al 0.5 In 0.5 The doping source of the first upper confinement layer is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.1-0.5μm; The P-type Al 0.5 In 0.5 The doping source of the second upper confinement layer is Cp2Mg or DEZn, and the doping concentration is 3E17-3E18 atoms / cm 3 , thickness is 0.5-2μm.

6. The semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 4, characterized in that: The n-type Al 0.5 In 0.5 The thickness of the P lower confinement layer is 0.9 μm and the doping concentration is 7E17 atoms / cm 3 ; The P-type Al 0.5 In 0.5 The thickness of the first upper confinement layer is 0.2 μm, and the doping concentration is 5E17 atoms / cm 3 ; The P-type Al 0.5 In 0.5 The thickness of the second upper confinement layer is 0.8 μm, and the doping concentration is 8E17 atoms / cm 3 .

7. The semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 1, characterized in that: The substrate is a GaAs substrate, the buffer layer is a GaAs buffer layer, and the lower transition layer is Ga 0.5 In 0.5 P lower transition layer, the lower waveguide layer is (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer, the upper waveguide layer is (Al x4 Ga 1-x4 ) y2 In 1-y2 P waveguide layer, the corrosion stop layer is P-type Ga x5 In 1-x5 P corrosion stop layer, the first upper transition layer is (Al 0.5 Ga 0.5 ) 0.5 In 0.5 The first upper transition layer is P, and the second upper transition layer is Ga 0.5 In 0.5 P second upper transition layer, the cap layer is a GaAs cap layer; Among them, 0.4≤x1≤1, 0.4≤y1≤0.6; 0.4≤x4≤1, 0.4≤y2≤0.6; 0.5≤x5≤0.

6.

8. The semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 7, characterized in that: The doping source of the GaAs buffer layer is Si2H6, and the doping concentration is 2E18-5E18 atoms / cm 3 , thickness is 0.1-0.3μm; The Ga 0.5 In 0.5 The doping source of the P lower transition layer is Si2H6, and the doping concentration is 5E17-2E18 atoms / cm 3 , thickness is 0.1-0.3μm; The x1 Ga 1-x1 ) y1 In 1-y1 The waveguide layer below P is not intentionally doped, 0.4≤x1≤1, 0.4≤y1≤0.6, x1 gradually changes from less than 1 to greater than or equal to 0.4, and the thickness is 60-200nm; The x4 Ga 1-x4 ) y2 In 1-y2 The waveguide layer on P is not intentionally doped, 0.4≤x4≤1, 0.4≤y2≤0.6, x4 gradually changes from greater than or equal to 0.4 to less than or equal to 1, and the thickness is 60-200nm; The P-type Ga x5 In 1-x5 The doping source of the P corrosion stop layer is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , 0.5≤x5≤0.6, thickness is 5-30nm; The 0.5 Ga 0.5 ) 0.5 In 0.5 The doping source of the first upper transition layer of P is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm; The Ga 0.5 In 0.5 The doping source of the second upper transition layer of P is Cp2Mg or DEZn, and the doping concentration is 1E18-3E18 atoms / cm 3 , thickness is 10-50nm; The doping source of the GaAs cap layer is CBr4 or DEZn, and the doping concentration is 3E19-1E20 atoms / cm 3 , thickness is 100-500nm; Further preferably, the thickness of the GaAs buffer layer is 0.2 μm and the doping concentration is 2E18 atoms / cm 3 ; The Ga 0.5 In 0.5 The thickness of the P lower transition layer is 0.1 μm and the doping concentration is 1E18 atoms / cm 3 ; The x1 Ga 1-x1 ) y1 In 1-y1 In the waveguide layer below P, x1 changes gradually from 0.95 to 0.5, y1 = 0.5, and the thickness is 100 nm; The x4 Ga 1-x4 ) y2 In 1-y2 In the waveguide layer on P, x4 changes gradually from 0.5 to 0.95, y2 = 0.5, and the thickness is 100nm; The P-type Ga x5 In 1-x5 The thickness of the P etch stop layer is 10 nm, x5 = 0.53, and the doping concentration is 2E18 atoms / cm 3 ; The 0.5 Ga 0.5 ) 0.5 In 0.5 The thickness of the first upper transition layer of P is 20nm, and the doping concentration is 1.2E18 atoms / cm 3 ; The Ga 0.5 In 0.5 The thickness of the second upper transition layer of P is 20nm, and the doping concentration is 1.5E18 atoms / cm 3 ; The GaAs cap layer has a thickness of 200 nm and a doping concentration of 5E19 atoms / cm 3 .

9. The method for preparing a semiconductor laser device for improving optical gain by utilizing quantum tunneling capability according to any one of claims 1 to 8, characterized in that: include: Growing the buffer layer, the lower transition layer, the lower confinement layer, and the lower waveguide layer in sequence on the substrate; The Ga is grown on the lower waveguide layer. x2 In 1-x2 P first quantum well; comprising: maintaining the temperature at 650±10°C, introducing TMIn, TMGa and PH3, growing the Ga on the lower waveguide layer x2 In 1-x2 P first quantum well; In the Ga x2 In 1-x2 The (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multi-quantum well barrier superlattice; comprising: maintaining the temperature at 650±10°C, introducing TMAl, TMIn, TMGa and PH3, and 1-x2 In x2 The (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 P strained multiple quantum well barrier superlattice; In the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 The GaP strained MQW superlattice was grown on x3 In 1-x3 P second quantum well; comprising: maintaining the temperature at 650 ± 10 ℃, introducing TMIn, TMGa and PH3, in the (Al a1 Ga 1-a1 ) b1 In 1-b1 P / (Al a2 Ga 1-a2 ) b2 In 1-b2 The GaP strained MQW superlattice was grown on x3 In 1-x3 P second quantum well; In the Ga x3 In 1-x3 The upper waveguide layer, the first upper confinement layer, the corrosion stop layer, the second upper confinement layer, the first upper transition layer, the second upper transition layer and the cap layer are sequentially grown on the P second quantum well.

10. The method for preparing a semiconductor laser device for improving optical gain by using quantum tunneling capability according to claim 9, characterized in that: The GaAs buffer layer, GaAs buffer layer, and GaAs layer are grown on the GaAs substrate. 0.5 In 0.5 P lower transition layer, n-type Al 0.5 In 0.5 P lower confinement layer, (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer; including: S1, placing a GaAs substrate in a growth chamber of an MOCVD device, heating the H2 environment to 720±10° C., and introducing AsH3 to perform surface heat treatment on the GaAs substrate; S2, slowly lowering the temperature to 680±10° C., with a cooling rate of no more than 30° C. / min, continuing to introduce TMGa and AsH 3 to grow a GaAs buffer layer on the GaAs substrate; S3, the temperature is maintained at 680±10° C., the growth is paused on the GaAs buffer layer, PH3 is introduced, and the growth is paused by stopping the V group source and the III group source for 3-30 seconds to deplete the As atoms in the growth chamber of the MOCVD equipment; S4, the temperature is maintained at 680±10°C, TMGa, TMIn and PH3 are introduced, and Ga is grown on the GaAs buffer layer. 0.5 In 0.5 P lower transition layer; S5, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, TMAl, TMIn and PH3 are introduced, and the Ga 0.5 In 0.5 Growth of n-type Al on the transition layer below P 0.5 In 0.5 P lower limiting layer; S6, the temperature is slowly changed to 650±10℃, the cooling rate is not higher than 60℃ / min, TMAl, TMIn, TMGa and PH3 are introduced, and the n-type Al 0.5 In 0.5 Growth on the confinement layer below P (Al x1 Ga 1-x1 ) y1 In 1-y1 P lower waveguide layer; Further preferably, in the Ga x3 In 1-x3 P second quantum well is grown in sequence (Al x4 Ga 1-x4 ) y2 In 1-y2 P upper waveguide layer, P type Al 0.5 In 0.5 P first upper confinement layer, P-type Ga x5 In 1-x5 P corrosion stop layer, P type Al 0.5 In 0.5 P second upper limiting layer, (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer, Ga 0.5 In 0.5 P second upper transition layer and GaAs cap layer; including: S7, the temperature is slowly changed to 700±10℃, the heating rate is not higher than 60℃ / min, and TMAl, TMIn, TMGa and PH3 are continuously introduced. x3 In 1-x3 The second quantum well of P is grown on x4 Ga 1-x4 ) y2 In 1-y2 P upper waveguide layer; S8, the temperature is maintained at 700±10°C, TMAl, TMIn and PH3 are continuously introduced, and in the (Al x4 Ga 1-x4 ) y2 In 1-y2 P-type Al is grown on the P waveguide layer 0.5 In 0.5 P first upper limiting layer; S9, the temperature is maintained at 700±10°C, TMGa, TMIn and PH3 are continuously introduced, and the P-type Al 0.5 In 0.5 P-type Ga is grown on the first upper confinement layer x5 In 1-x5 P corrosion stop layer; S10, the temperature is maintained at 700±10°C, TMAl, TMIn and PH3 are continuously introduced, and the P-type Ga x5 In 1-x5 Growth of P-type Al on P Etch Stop Layer 0.5 In 0.5 P second upper limiting layer; S11, the temperature is gradually changed to 680±10℃, the cooling rate is not higher than 60℃ / min, TMAl, TMIn, TMGa and AsH3 are introduced, and the P-type Al 0.5 In 0.5 The second upper confinement layer growth (Al 0.5 Ga 0.5 ) 0.5 In 0.5 P first upper transition layer; S12, the temperature is maintained at 680±10℃, the cooling rate is not higher than 60℃ / min, TMIn, TMGa and AsH3 are introduced, and the (Al 0.5 Ga 0.5 ) 0.5 In 0.5 Ga is grown on the first upper transition layer 0.5 In 0.5 P second upper transition layer; S13, lower the temperature to 540±10°C, with the cooling rate not exceeding 40°C / min, continue to introduce TMGa and AsH3, 0.5 In 0.5 A GaAs cap layer is grown on the P second upper transition layer.

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